Help! Problems Installing Microsoft Security Essentials

The installation of Microsoft Security Essentials is a quick process but in some cases, the installation will fail with errors. Read this article to solve the Microsoft Security Essentials installation errors.

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Overview

When installing the free antivirus program by Microsoft for Windows XP, Vista and Windows 7, you may receive Microsoft Security Essentials installation errors, the installation will not continue or the error code is 0x80070643. Follow the steps below to succeed to installing the antivirus software.

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How to solve Microsoft Security Essentials Installation Errors?

How to solve Microsoft Security Essentials Installation Errors?

To possibly solve the failed installation of Microsoft Security Essentials, use the steps below in the order shown.

Step 1: Remove any existing antivirus program by other vendors

Open the Add/Remove Programs utility in Windows or simply type appwiz.cpl in the Run box of Windows XP or the Search box in Windows 7 and Vista. Locate the third party antivirus program.

If you don’t find any antivirus program in the list of installed programs, download AppRemover. AppRemover is a standalone security tool remover. It has the option to scan the system for leftovers from any already uninstalled security programs. If it detects the registry keys, files, and folders of another antivirus program, proceed to clean-up the system using AppRemover. Note that you don’t have to use AppRemover if you prefer to use the clean-up utility or removal tool of the already uninstalled antivirus program vendor:

If your already removed antivirus is not listed, check the vendors’ website or simply use AppRemover.

Reboot the PC and try installing Microsoft Security Essentials again.

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Step 2: Verify the status of Windows Installer service

Open the Services console in Windows by typing services.msc in Run/Search box.

Locate Windows Installer service. Double-click the service to bring up the properties. If the status is “Stopped", click the “Start" button. Click OK to apply the command then close the Services console. Try to install Microsoft Essentials.

If the status of Windows service is “Started", close the Services console.

Type cmd in Run/Search box then press enter to open the Command Prompt. In Vista and Windows 7, right-click cmd in the list of programs that the Search utility will display then select “Run as admin" to continue using Command Prompt.

In Command Prompt window, type this command msiexec /regserver then press enter in the keyboard. Note that there is no confirmation to see if the command failed or succeeded. Simply close the Command Prompt window after pressing the enter key.

Try installing Microsoft Security Essentials again.

Note: If you are using Windows XP, verify that you have Windows Installer v3.1 or higher version. If you have a version of Windows Installer lower than v3.1, proceed to download the new version for your operating system by downloading it from the Microsoft website.

If none of the above steps help in solving the installation of Microsoft Security Essentials, proceed to submitting an online support case to Microsoft. If you are in the U.S. or Canada, you may also call Microsoft at 1-866-727-2338 for support. A support forum for Microsoft Security Essentials is also available, in case you want to see if other people have shared any work-arounds to solve the installation process of the antivirus program by Microsoft.

For end-users who only want to fix Microsoft Security Essentials by resetting its settings, try using Fix MSE Utility by The Windows Vista Club.